Higher-income persons are more likely to meet retirement income goals, says a study that adds that lower-income persons in many cases would be better off delaying their retirement to later than they expected.

The study by the Center for Retirement Research examined data on couples who had reached age 58, when retirement is generally within sight, and used the common benchmark of needing to replace 80 percent of pre-retirement income as a retiree.

After dividing that population into quarters according to income, it found that 95 percent of the lowest-earning quartile would be unable to meet that retirement income goal at age 60, compared with 86 percent in the top quartile. At age 62, the figures were 78 and 64 percent, respectively; at age 65 61 and 46 percent; and at age 70 the difference was virtually gone, 22 to 21 percent.

The study similarly showed that the difference between their target date to stop working and the date they would need to wait to in order to achieve their retirement income goals decreased with income levels.

It added that working longer may not be a realistic option for lower-income households in general, however.